Scientists prove that fears and memories can be inherited via sperm

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Darwin’s theory of evolution, that of blind mutation and natural selection, is a pillar of modern day science. Yet to many, it remains deeply dissatisfying for one simple reason — it lacks biological provisioning to pass to our children anything that we have won, or lost, by our exertions through the course of life. While scientists have documented numerous cases where the children of significantly traumatized parents have in fact inherited specific predispositions, direct experimental evidence for this phenomenon, and a plausible mechanism, has until now been lacking. Reporting in the current issue of Nature Neuroscience, researchers have now shown that mice can inherit the acquired fears of their fathers through some mysterious reprogramming occurring within the family jewels.

The way that the researchers were able to constrain the range of possible influences of parent upon child, or in this case from mouse to pup, was to separate them entirely by doing artificial insemination. In that way, the only source of information transfer between the two was the sperm itself. The “fear” or at least the “event” that the experimenters chose to transfer was an association of the smell of a chemical known as acetophenone, which was paired with a slightly discomforting electric shock to the their feet. Acetophenone is a commonly used chemical within the larger science of smell that has a citrus, orange-like smell to it. While there is no perfect stimulus (in higher concentrations acetophonone is actually a hypnotic), it is as good as any for the experiments at hand.

When the researchers tested the pups of the traumatized dads for a startle response to different smells, the acetophenone stimulus had a big effect which was not seen in controls. To emphasize here, these pups never actually learned from any previous footshock trials that the acetophonone was bad news, they just somehow knew it because of who there were. If we accept these results at face value, (and there is simply no further progress if we choose not to) than the question becomes, what in the sperm ferries this experience? It is likely that there are many overlapping mechanisms, existing on many levels. First, there could be changes to the actual DNA sequence, or significant tracts of it. One example for this would be by some kind of viral transformation or directed mutation. Second, there could be so called “epigenetic” modifications to the sequence — basically additional bits that get set by various enzymes acting to modify the DNA base pairs. And third, some other chemical influence affecting global properties of the sperm interior, which possibly gets transmitted to the egg along with the raw genetic cargo.

The researchers focused on mechanism number two here, for several reasons. In this case, sperm happen to carry a similar receptor for acetophenone as that which the nose uses to detect it in the first place. Furthermore, they could look for epigenetic modifications to the control region of the actual gene in the sperm which codes for the acetophone detector. The full fate of odorants like acetophenone, once they are inhaled, still remains to be seen. The idea that acetophone gets into the bloodstream and then to the sperm may have a certain appeal, but it is difficult to actually prove that unambiguously without many controls.

The reason a lot of neuroscientists are excited about this work is that the researchers were also able to show that the regions of the pup’s smell-brain (the olfactory glomeruli) that specifically process acetophonone were much larger than normal. These astonishing effects were also found in the grandpups of the original mouse which underwent the fear conditioning. What confounds is that the changes that took place in the sperm, (or gauged another way, the selection from a pre-existing palette of freshly-minted sperm options), have somehow underwritten the construction of the brain in the next generation. Or so it would appear.

So it seems we now have an experimental base established, through which various mechanisms of the transmission of specific experiences to offspring can be further probed. The actual bandwidth, in bits per second, between brain (which presumably acts as the main detector and controller of experienced-based modifications) and balls is not known. There are certainly nerves that feed the gonads, and also various chemicals of influence that are timely spritzed into the bloodstream. Additionally, there can be fine-scale temperature regulation within the deep vaults of the seminiferous tubule file system (the hatchery bank where sperm are halved) that directly bear on the final product.

We should note that beyond the controlled setting of a caged laboratory mouse isolated from nearly every other possible experience in life, such effects would probably be harder to observe. As humans, we absorb and respond to a constant and diverse onslaught of potentially significant stimuli in any given day. Reliably transmitting any one microexperience in isolation directly to our gonads would be difficult to imagine. However, if males did not in fact dump some level of environmental experience into their sperm each day, then what other reason has been offered to date to explain the prolific turnover of these minions?

Or in other words, sperm must retain some adaptive capacity for the transmission of the instantaneous fitness of the larger collective body, at least on the scale of threat, perhaps extending into other pass-fail social trials. In this larger view, it is important to recognize that the mice in these particular experiments could only do just one thing in their entire life — smell acetophonone when shocked, and put that into next generation. That, they seemed to have done.

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Sipho Mfungi

It’s more correct to say that Darwin’s theory of evolution is a pillar in the halls of stupidity . It’s not science. Also the fact that mental and spiritual phenomena can be passed on to offspring is something the Bible clearly tells us. “Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all people – Romans 5:12″

Morgan Glassco

You think this test and the people who performed it come from the “halls of stupidity”? Please share your contributions to the science community. You’ve done nothing more than cite a book.

Sipho Mfungi

yes I’ve cited a book, but have these scientists not cited a book also, Darwin’s book? What have YOU contributed to science that you ask me that question? this is a comments section my friend. free for all. don’t squash dissent. comment on the article, or on the comment, not on the person

Morgan Glassco

As you said, its a free for all. P.S. the scientist didn’t say anything about Darwin, the author of the article did.

You have chosen to show your fears in your beliefs with name calling. None of it added to the topic, which is science, not blind faith.

Sipho Mfungi

you obviously didn’t read the paper linked to at the bottom. it clearly says “We propose that the maternal TNF–milk chemokine pathway evolved to promote offspring adaptation to post-weaning environmental challenges and competition.” so you’re not making sense here.

Morgan Glassco

You are correct I did not red the linked article. My apologies. But who really isn’t making sense here? The person that just writes off actual science for belief in a fiction book or the guy who didn’t read an additional article? And before you respond, keep in mid you agree with me about religion 99% of the time until we get on the topic of YOUR religion.

Sipho Mfungi

rewind a bit. i did not say that what these scientists did is rubbish. my problem is with the darwinian interpretation of the experiment. is it so far fetched to suggest alternative explanations for observed events? the bible is a fiction book? where’s your proof, or are you just doing the same thing you’re accusing me of? anyways, Jesus loves you Morgan Glassco, and Netmonger, and strangelove91. I pray you get saved soon.

http://GPlus.to/Abhisshack Abhisshack

You are nothing more than a fucking stupid Relitard (religious retard)
“It’s better to keep your mouth shut and appear stupid than open it and remove all doubt”

― Mark Twain

csgo1337

Relitard? You realize when you had to explain what this meant it just made you look ignorant. Maybe choose a better word for Religious Retard? One that you don’t have to explain. One people already would understand :)

http://GPlus.to/Abhisshack Abhisshack

it is my generosity that i’m explaining it otherwise how would relitard like you would understand it , because your brain is so small i need to explain it in detail otherwise how would that enter in your empty head. if you spend more time reading other stuff rather that the fairtytale book ‘The Bible’ then you would have knew that relitard is a very common word not created by me.
Now correct my grammar because ifif you can’t win an argument correct their grammar instead

Just to inform you i am Agnostic and do not believe exactly what is in the bible. I love how you automatically assume that i am what you call a Relitard just for pointing out your utter stupidity… I find it very interesting you use the Urban Dictionary… HaHa

The pure ignorance i find on this website is just absolutely appalling. I just can’t understand why all these super intelligent beings such as yourself are limited to being on a website like this? Shouldn’t you be writing a book on your vast knowledge of Theology or should i say Anti-Theology. You sure are quick to jump the gun on Bible Bashing yet i have seen nothing to backup your statements. Not that i personally want to hear your theories on religion anyway but next time just come prepared to defend your statements before getting into a argument.

I would also like to point out that people shouldn’t have to correct your grammar… Someone with such knowledge as yourself should be “spot” on with this…

Netmonger

No they didnt just ‘cite a book’. And the burden isnt on us to explain all this to you. If you want to understand evolution, then go back to school and study biology. But dont go posting comments in an online forum when you clearly have no understanding of the topic. Its ridiculous.

Ibrinar

Um you do know that while Darwin started it the research moved on and there is no reason to quote his books (beside nods to history) instead of quoting modern works?

It’s really fascinating how religuous fundamentalists always seem to think that everything about evolution comes from Darwin, yes he started the field and did some impressive work. No his work isn’t state of the art, since it was only the beginning.

strangelove91

Sipho Mfungi
: Most of your posts on this site deal with some religious crap – you either insult catholics or atheists, or you need to quite bible passages ad nauseam. Please understand that nobody cares about your ramblings. You are a big ZERO. You lack decency and education. Having internet access in your African hovel doesn’t automatically make you respectable.

We “get it”: you’re just another third-worlder with a chip on his shoulder and a shoddy education (in which religion has played too large of a role for your own good). Now piss off, and go get stomped by an elephant or something… hurry up to meet your lord Jesus quicker, and spare the rest of us of your stupidity.

Ray C

I think he has the right to his religion. That being said calling something stupidity does cross the line. From your post, it appears he goes overboard at times

Morgan Glassco

They lash out out of fear. Their beliefs alone are not strong enough and need others to support them or to attempt to hurt others with different beliefs. Childish really.

Netmonger

Are you a scientist? But you think you can hop online and call a 100+ years of hard work ‘stupid’ – without a single bit of evidence – and that suddenly makes it so? And what this: Your ‘proof’ is a quote from the Bible?!? Are you kidding me?!? The Bible is a work of *FICTION* written 2000 years ago when life expectancy was 30, there was no electricity, and people thought the world was flat. Get a grip. Evolution isnt a debate. Its accepted scientific theory. And its happening all the time.

dns7950

LOL! I have no idea how you think any bible quote is in any way relevant to this article. What are you doing on extremetech if you don’t believe in science? I really hope you’re just a stupid troll.

convolution

Obvious troll much?

Heath Parsons

Alright, first of all, if you want to quote the Bible, do so without assumption of literature on anything other than the literature speaks of (for example, assuming phobias are also passed down with sin). Second, Darwin was a genius of his time. Origin of Species wasn’t the only work he has written, and even he started questioning his work at the end of his life. He revolutionized our understanding of life (by life, I don’t mean spiritual) and was the start of a huge trek into the origins of life.

Furthermore, what this passage means is that “sin nature” or the tendency toward sin is passed down, not sin itself as you assumed. This is how Jesus avoids being a sinner from birth. He was a descendant of Mary (on earth), who was a descendant of Adam, so by your reference (out of context and misinterpreted), you are assuming he should have had “original sin” passed down in genetics, but he didn’t. People try to find materialistic explanations for supernatural things, but truth and logic are not material in nature. Sin is not intrinsically bound to genetics. Demons sin, and they are not confined to human DNA.

Therefore, this article is not about how the tendency for sin is passed down (as that is explicitly told in the Bible by the passage you referenced), but how fear is passed down. Two different things. Spiritual phenomena cannot be passed down through genetics as it is immaterial. Mental phenomena, perhaps, and that is what these researchers are testing.

For those bashing on the Bible, you cannot understand the entirety of the Bible without the Holy Spirit enlightening you on its meaning and structure. Be cautious when applying only material explanations to a world that is both spiritual and material.

Morgan Glassco

Very interesting read. But to sum up my feelings, it is “duh”. I believe we all knew or were inclined to believe this was happening in some way. I look forward to the developments this insight will bring.

Ray C

Why should this be a surprise. Our bodies are a collection of organs, tissues, and signals. Everything we think or do can have an effect on another part of the body. It can even make some changes to our own DNA. This is no different than being shocked or coming into contact with some agent, it effecting your DNA, then passing that change on.

jhambi

The whole point of the article is that what you are describing was not proven and finding evidence for that is infact a huge deal. There was NO known mechanism for this in the past. Changing DNA is not actually that common. Unless it is something like a mutagen/teratogen, most stuff you come into contact with should not be changing your DNA.

Phobos

I guess it’s no different if you inherit well not inherit but more likely to develop diabetes if you have family record.

jhambi

It is very different from that. The DNA that codes for the genes that determine an increased likely hood to have diabetis are there from the start. They are large coding regions that are (relatively) well understood. This is some new mechanism that is changing something well after conception and allowing you to pass information that is not directly expressed in development.

Dozerman

This isn’t as surprising as you’d think. It would be expected that a mechanism like this would evolve to allow for quicker adaptations. Slower adaptations be selected against in the long run, so this was bound to exist.

They proved a connection… Was the traumatized father still alive? Could be a subconscious connection, quantum entanglement?

JD Rahman

Good point. This study is jumping to conclusions based on what we know without considering that there are already things that we see that we cannot explain, such as entanglement.

Dozerman

Although we do not understand everything in the universe at this point, I think that it’s safe to say that entanglement has nothing to do with this, as well as some form of telekenisis, a transfer of souls, or whatever else. Based off of what we do know now, and the evidence presented to us, I think that it’s safe to say that this is genetic.

Dozerman

Although we do not understand everything in the universe at this point, I think that it’s safe to say that entanglement has nothing to do with this, as well as some form of telekenisis, a transfer of souls, or whatever else. Based off of what we do know now, and the evidence presented to us, I think that it’s safe to say that this is genetic.

DeeDee2011

Which may explain a lot about the intergenerational transmission of PTSD in humans. I always thought it was from being raised by a traumatized parent. Now I wonder.

JD Rahman

What if this phenomenon is valid for other things.
Take for example, social and cultural behavior?
What if accepting homosexuality increases the chances of your offspring being lesbian/gay/bi?
Or being racist increases the chance of having children susceptible to racist tendencies?

This would mean a society can progressively get better or worst based on the actions and beliefs of parents long before they became parents. Follow this through generation after generation and in time, we would end up with a super or purebred society of whatever traits were strong in our forefathers.

Vux777

What if accepting homosexuality increases the chances of your offspring being lesbian/gay/bi?

what if someone is homophob, and there is a chance that his/her offspring will also be…
oh wait….

Glenn Scott

I would be interested to see what the effects would be if the female of the species underwent these same tests.

Mackenzie

All these arguments of religion and science. Oh dear. I just marvel at the beauty of life and our advancements. Let us drop our tribulations of disagreement and realize how uniquely gorgeous our planet is and the amazing life it harbors. Be it a deity or something else entirely that created our planet, it is here for us to love and cherish.

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